Method of forming a hardened surface on a substrate

ABSTRACT

The invention includes a method of producing a hard metallic material by forming a mixture containing at least 55% iron and at least one of B, C, Si and P. The mixture is formed into an alloy and cooled to form a metallic material having a hardness of greater than about 9.2 GPa. The invention includes a method of forming a wire by combining a metal strip and a powder. The metal strip and the powder are rolled to form a wire containing at least 55% iron and from two to seven additional elements including at least one of C, Si and B. The invention also includes a method of forming a hardened surface on a substrate by processing a solid mass to form a powder, applying the powder to a surface to form a layer containing metallic glass, and converting the glass to a crystalline material having a nanocrystalline grain size.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.10/172,095, filed Jun. 13, 2002, now U.S. Pat. No. 6,689,234, issuedFeb. 10, 2004, which is a continuation-in-part of U.S. patentapplication Ser. No. 09/709,918, filed on Nov. 9, 2000, now U.S. Pat.No. 6,767,419, issued Jul. 27, 2004, the disclosures of both of whichare hereby incorporated by reference.

GOVERNMENT RIGHTS TO THE INVENTION

This invention was made with United States Government support undercontract number DE-AC07-99ID13727, awarded by the United StatesDepartment of Energy. The United States Government has certain rights inthe invention.

TECHNICAL FIELD

The invention pertains to hard metallic materials and methods of forminghard metallic materials.

BACKGROUND OF THE INVENTION

Steel is a metallic alloy that can have exceptional strengthcharacteristics, and which is accordingly commonly utilized instructures where strength is required or advantageous. Steel can beutilized, for example, in the skeletal supports of building structures,tools, engine components, and protective shielding of modern armaments.

The composition of steel varies depending on the application of thealloy. For purposes of interpreting this disclosure and the claims thatfollow, “steel” is defined as any iron-based alloy in which no othersingle element (besides iron) is present in excess of 30 weight percent,and for which the iron content amounts to at least 55 weight percent,and carbon is limited to a maximum of 2 weight percent. In addition toiron, steel alloys can incorporate, for example, manganese, nickel,chromium, molybdenum, and/or vanadium. Accordingly, steel typicallycontains small amounts of phosphorus, carbon, sulfur and silicon.

Steel comprises regular arrangements of atoms, with the periodicstacking arrangements forming three-dimensional lattices that define theinternal structure of the steel. The internal structure (sometimescalled “microstructure”) of conventional steel alloys is always metallicand polycrystalline (consisting of many crystalline grains). Bothcomposition and processing methods are important factors that effect thestructure and properties of a steel material. In conventional steelprocessing, an increase in hardness can be accompanied by acorresponding decrease in toughness. Steel material produced byconventional methods that increase the hardness of the composition canresult in a steel material that is very brittle.

Steel is typically formed by cooling a molten alloy. For conventionalsteel alloys, the rate of cooling will determine whether the alloy coolsto form an internal structure that predominately comprises crystallinegrains or, in rare cases, a structure that is predominately amorphous (aso called metallic glass). Generally, it is found that if the coolingproceeds slowly (i.e., at a rate less that about 10⁴ K/s), large grainsizes occur, while if the cooling proceeds rapidly (i.e., at rategreater than or equal to about 10⁴ K/s) microcrystalline internal grainstructures are formed, or, in specific rare cases not found inconventional steel alloy compositions, an amorphous metallic glass isformed. The particular composition of a molten alloy generallydetermines whether the alloy solidifies to form microcrystalline grainstructures or an amorphous glass when the alloy is cooled rapidly.

Both microcrystalline grain internal structures and metallic glassinternal structures can have properties that are desirable in particularapplications for steel. In some applications, the amorphous character ofmetallic glass can provide desired properties. For instance, someglasses can have exceptionally high strength and hardness. In otherapplications, the particular properties of microcrystalline grainstructures are preferred. Frequently, if the properties of a grainstructure are preferred, such properties will be improved by decreasingthe grain size. For instance, desired properties of microcrystallinegrains (i.e., grains having a size on the order of 10⁻⁶ meters) canfrequently be improved by reducing the grain size to that ofnanocrystalline grains (i.e., grains having a size on the order of 10⁻⁹meters). It is generally more problematic, and not generally possibleutilizing conventional approaches, to form grains of nanocrystallinegrain size than it is to form grains of microcrystalline grain size.

It is desirable to develop improved methods for forming nanocrystallinegrain size steel materials. Further, as it is frequently desired to havemetallic glass structures, it is desirable to develop methods of formingmetallic glasses. Still further, it is desirable to develop methods ofprocessing steel that can achieve an increased hardness without acorresponding loss of toughness.

SUMMARY OF THE INVENTION

In one aspect, the invention encompasses a method of producing a hardmetallic material. A mixture of elements containing at least about 55%iron by weight, and at least one of B, C, Si and P is formed into analloy and the alloy is cooled at a rate of less than about 5000 K/s toform a metallic material having a hardness of greater than about 9.2GPa. In one aspect, the invention encompasses a metallic materialcomprising at least 55% iron and at least one of B, Si, P and C. Thematerial has a total element composition of fewer than eleven elements,excluding impurities, has a melting temperature between about 1100° C.and about 1250° C. and has a hardness of greater than about 9.2 GPa. Inone aspect, the invention encompasses a method of forming a wire. Ametal strip having a first composition and a powder having a secondcomposition are rolled/extruded together to combine the firstcomposition and the second composition to form a wire having a thirdcomposition. The third composition contains at least 55% iron, byweight, and from two to seven additional elements including at least oneof C, Si and B.

In one aspect, the invention encompasses a method of forming a hardenedsurface on a substrate. A solid mass having a first hardness isprocessed to form a powder. The powder is applied to a surface of asubstrate to form a layer having a second hardness. At least some of thelayer contains metallic glass that may be converted to a crystallinematerial having a nanocrystalline grain size. The converting of themetallic glass to a crystalline material hardens the layer to a thirdhardness that is greater than the first hardness and greater than thesecond hardness.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below withreference to the following accompanying drawings.

FIG. 1 is a block-diagram flow chart view of a method encompassed by thepresent invention.

FIG. 2 is a block-diagram flow chart view of a processing methodencompassed by the present invention.

FIG. 3 is a SEM micrograph of a metallic powder produced by methods ofthe present invention.

FIG. 4 is a fragmentary, diagrammatic, cross-sectional view of ametallic material at a preliminary processing step of a method of thepresent invention.

FIG. 5 is a view of the FIG. 4 metallic material shown at a processingstep subsequent to that of FIG. 4.

FIG. 6 is a fragmentary, diagrammatic, cross-sectional view of ametallic material substrate at a treatment step of a process encompassedby the present invention.

FIG. 7 shows examples of coatings comprising Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄formed by high velocity oxy-fuel deposition onto 4340 alloy steel, 13-8stainless steel and 7075 aluminum substrates.

FIG. 8 shows a cross-section indicative of a porosity of aFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ coating from FIG. 7.

FIG. 9 shows cross-sections demonstrating porosities of coatingscomprising (Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ deposited by plasmadeposition (Panel A), high velocity oxy-fuel deposition (Panel B), andWire-Arc deposition (Panel C).

FIG. 10 illustrates an x-ray diffraction scan of a free surface of a 330micron thick, high velocity oxy-fuel deposited coating comprisingFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄.

FIG. 11 illustrates x-ray diffraction scans of a free surface (Panel A)and a substrate-interface surface (Panel B) of a 1650 micron thick,plasma-sprayed coating comprising Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄.

FIG. 12 illustrates an x-ray diffraction scan of a free surface of a0.25 inch thick coating formed by wire-arc spraying utilizing a wirehaving the composition (Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂.

FIG. 13 illustrates data obtained from differential thermal analysis ofatomized powder (top graph), a high velocity oxy-fuel coating (middlegraph) and a plasma sprayed coating of the compositionFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄. The graph curves show glass to crystallinetransitions of the tested forms of the composition and the meltingtemperature of the composition.

FIG. 14 illustrates differential scanning calorimetry data acquired froma 0.25 inch thick coating formed by wire-arc deposition of compositionFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄. The graph shows the glass to crystallinetransition of the coating.

FIG. 15 shows SEM micrographs and corresponding selected areadiffraction patterns of a metallic material produced from a compositioncomprising (Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂ by methods of the presentinvention after heat treatment for one hour at 700° C. (Panel A), 750°C. (Panel B) or 800° C. (Panel C).

FIG. 16 shows SEM micrographs and corresponding selected areadiffraction patterns of a metallic material produced from a compositioncomprising (Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ by methods of thepresent invention after heat treatment for one hour at 600° C. (PanelA), 700° C. (Panel B) or 800° C. (Panel C).

FIG. 17 is an SEM micrograph of a coating comprisingFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ formed by methods of the present inventionutilizing HVOF deposition followed by treatment for one hour at 600° C.

FIG. 18 illustrates measured (Panel A) and Rietveld refined (calculated,Panel B) x-ray diffraction patterns of a high velocity oxy-fuel coatingcomprising the composition (Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ afterheat treating the coating for one hour at 750° C.

FIG. 19, Panel A, shows an example of a strip of steel coated withFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ to a thickness of approximately 200 microns. Thecoating was applied using high-velocity oxy-fuel deposition. Panel B andPanel C show the effects on the coating during bending of the coatedstrip.

FIG. 20 shows a flat plate of base-metal with an approximately 200micron thick coating of Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ formed by high velocityoxy-fuel deposition. Identically formed plates were used to show a plateas formed (Panel A), a plate after being repeatedly hammered on thecoating side (Panel B) or on the substrate side (Panel C), and a plateafter sever plastic deformation (Panel D).

FIG. 21 illustrates true-stress/true-strain measurements obtained frommetallic ribbons comprising metallic glass of the composition(Fe_(0.8)Cr_(0.2))₈₁B₁₇W₂. The graph curves reflect data obtained at 20°C. at a strain rate of 10⁻³ s⁻¹ (Panel A); at 450° C. (Panel B) atstrain rates of 10⁻⁴ s⁻¹ (closed circles) and 10 ⁻² s⁻¹ (open circles);at 500° C. (Panel C) at strain rates of 10⁻⁴ s⁻¹ (closed circles), 10 ⁻²s⁻¹ (open circles) and 10⁻¹ s⁻¹ (triangles); and at 550° C. (Panel D) atstrain rates of 10⁻¹ s⁻¹ (open circles) and 10 ⁻² s⁻¹ (closed circles).

FIG. 22 illustrates true-stress/true-strain measurements obtained frommetallic ribbons of the composition (Fe_(0.8)Cr_(0.2))₈₁B₁₇W₂ aftercrystallization. The curve reflects data obtained at 750° C. at a strainrate of 10⁻⁴ s⁻¹. Crystallization was achieved by heating thecomposition to above the crystallization temperature but lower than themelting temperature of the composition.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

This disclosure of the invention is submitted in furtherance of theconstitutional purposes of the U.S. Patent Laws “to promote the progressof science and useful arts” (Article 1, Section 8).

The invention encompasses methodology for forming metallic glass steelmaterials and for forming steel materials having nanocrystalline scalecomposite microstructures, methods of utilizing such steel materials,and also encompasses the steel material compositions. A processencompassed by the present invention is described generally withreference to the block diagram of FIG. 1. At an initial step (A) amixture of elements is formed. Such mixture comprises a steelcomposition. An exemplary mixture comprises at least 55% iron, byweight, and can comprise at least one element selected from the groupconsisting of B, C, Si and P. In particular aspects of the presentinvention, the mixture will comprise at least two of B, C and Si. Themixture can comprise B, C and Si, and in particular embodiments themixture can comprise B, C and Si at an atomic ratio of B₁₇C₅Si₁. Inparticular aspects of the present invention, the mixture can contain atleast one transition metal that can be, for example, selected from thegroup consisting of W, Mo, Cr and Mn. In addition, the mixture cancontain one or more of Al and Gd.

Mixtures of the present invention preferably comprise fewer than elevenelements, and can more preferably comprise fewer than nine elements.Additionally, the mixtures can comprise as few as two elements. Inparticular embodiments, the mixture can consist essentially of or canconsist of fewer than eleven elements. Further, the mixture can consistessentially of, or can consist of as few as two elements. Generally,mixtures of the present invention are composed of from four to eightelements.

Exemplary mixtures that can be utilized in methodology of the presentinvention are: Fe₆₃Mo₂Si₁, Fe₆₃Cr₈Mo₂, Fe₆₃Mo₂Al₄,(Fe_(0.8)Cr_(0.2))₈₁B₁₇W₂, (Fe_(0.8)Mo_(0.2))₈₃B₁₇, Fe₆₃B₁₇Si₁,Fe₆₃Cr₈Mo₂C₅, Fe₆₃Mo₂C₅, Fe₈₀Mo₂₀, Fe₆₃Cr₈Mo₂B₁₇, Fe₈₃B₁₇, Fe₆₃B₁₇Si₅,Fe₆₃B₁₇C₂, Fe₆₃B₁₇C₃Si₃, (Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂, Fe₆₃B₁₇C₃Si₅,Fe₆₃B₁₇C₂W₂, Fe₆₃B₁₇C₈, Fe₆₃B₁₇C₅, (Fe_(0.8)Cr_(0.2))₇₈Mo₂W₂B₁₂C₅Si₁,Fe₆₃B₁₇C₅W₅, Fe₆₃B₁₇C₅Si₅, (Fe_(0.8)Cr_(0.2))₇₆Mo₂W₂B₁₄C₅Si₁,(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂, Fe₆₃Cr₈Mo₂B₁₇C₅,(Fe_(0.8)Cr_(0.2))₇₅Mo₂B₁₇C₅Si₁, Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄,(Fe_(0.8)Cr_(0.2))₇₅W₂B₁₇C₅Si₁, Fe₆₃B₁₇C₅Si₁,(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₇C₅Si₁, (Fe_(0.8)Cr_(0.2))₇₂Mo₂W₂B₁₇C₅Si₁Gd₁,(Fe_(0.8)Cr_(0.2))₇₁Mo₂W₂B₁₇C₅Si₁Gd₂, and(Fe_(0.8)Cr_(0.2))₇₄Mo₂W₂B₁₇C₄Si₁.

At step (B) of FIG. 1, the mixture can be formed into an alloy. Alloyformation step (B) can comprise, for example, melting a compositionunder an argon atmosphere.

At step (C) of FIG. 1, the alloy can be cooled to form a hard materialcomprising a solid mass. Cooling of conventional steel alloys to formsolid materials typically comprises cooling at a rate of at least about5000 K/s, in order to achieve a hard steel solid. For purposes of thepresent description, cooling at a rate of at least about 5000 K/s can bereferred to as rapid cooling. Rapid cooling can be accomplished by anumber of different processes, including, for example, melt-spinning,gas atomization, centrifugal atomization, water atomization and splatquenching. Alternatively, Step (C) of FIG. 1 can comprise fast coolingor alternatively can comprise slow cooling (cooling at a rate of lessthan or equal to about 5000 K/s) to form a hard solid material. Slowcooling of an alloy can preferably comprise cooling at a rate of lessthan about 5000 K/s and can utilize methods such as arc-melting,casting, sand casting, investment casting, etc. The rate of cooling andthe resulting hardness of the hard metallic material can vary dependingon the particular composition of the mixture used to form the alloy. Inparticular embodiments, a hard metallic material formed by the methodsof the present invention can comprise a hardness of greater than about9.2 GPa. Additionally, contrary to conventional steels compositions thatare rapidly cooled to achieve high hardness, particular alloycompositions of the present invention can achieve extreme hardness(greater than about 9.2 GPa) by slow cooling.

The hard solid material formed in step (C) of FIG. 1 can comprise amelting temperature of, for example, between about 1100° C. and about1550° C. The hard solid material formed in step (C) of FIG. 1 is notlimited to a specific form and can be, for example, a cast materialincluding but not limited to an ingot form. The formation of a hardsolid material by the processing steps shown in FIG. 1 can comprisestandard metallurgy techniques including, but not limited to,arc-melting, investment casting, sand casting, spray forming and sprayrolling.

Measured hardness (GPa) for as-cast ingots of selected compositionsencompassed by the present invention are reported in Table 1. The ingotswere cut in half with a diamond saw, metallo-graphically mounted, andtested for hardness, with each reported hardness value representing anaverage of ten measurements. As shown in Table 1, the resulting as-castingots can comprise a hardness as high as 14.9 GPa.

Although the cooled alloy in solid mass form can comprise a very highhardness, the hardness can be accompanied by very low toughness. Due tothe low toughness, ingots formed as described above can be very brittleand can shatter upon impact, as, for example, when struck with a hammer.However, contrary to an observed decrease in toughness that accompaniesincreased hardness in materials produced by conventional steelprocessing, further processing of the solid mass material by methods ofthe present invention (discussed below) can produce materials havingboth extreme hardness and increased toughness relative to the ingotform.

TABLE 1 Hardness of Ingots Ingot Composition Hardness (GPa) Fe₆₃B₁₇C₃Si₃10.3 (Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂ 10.8 Fe₆₃B₁₇C₃Si₅ 11.1 Fe₆₃B₁₇C₂W₂ 11.2Fe₆₃B₁₇C₈ 11.9 Fe₆₃B₁₇C₅ 12.1 (Fe_(0.8)Cr_(0.2))₇₈Mo₂W₂B₁₂C₅Si₁ 12.1Fe₆₃B₁₇C₅W₅ 12.3 Fe₆₃B₁₇C₅Si₅ 12.3 (Fe_(0.8)Cr_(0.2))₇₆Mo₂W₂B₁₄C₅Si₁12.3 (Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ 12.3 Fe₆₃Cr₈Mo₂B₁₇C₅ 12.5(Fe_(0.8)Cr_(0.2))₇₅Mo₂B₁₇C₅Si₁ 12.7 Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ 13.2(Fe_(0.8)Cr_(0.2))₇₅W₂B₁₇C₅Si₁ 13.4 Fe₆₃B₁₇C₅Si₁ 13.7(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₇C₅Si₁ 14.0(Fe_(0.8)Cr_(0.2))₇₂Mo₂W₂B₁₇C₅Si₁Gd₁ 14.4(Fe_(0.8)Cr_(0.2))₇₁Mo₂W₂B₁₇C₅Si₁Gd₂ 14.7(Fe_(0.8)Cr_(0.2))₇₄Mo₂W₂B₁₇C₄Si₁ 14.9

Additional and alternative processing of the alloy of FIG. 1 step (B)and the hard solid material of FIG. 1 step (C) is described generallywith reference to the block diagram of FIG. 2. An alloy according tomethods of the present invention can comprise a molten alloy as shown inFIG. 2 step (D). The molten alloy can be solidified in step (E) by rapidcooling or by slow cooling according to the methods discussed above. Thesolidified material can be subjected to a further processing step (F) toform a powder. Alternatively, the molten alloy of step (D) can bedirectly subjected to powder formation step (F).

Processing the solid material step of step (E) into a powder form cancomprise, for example, various conventional grinding or milling steps oratomization methods such as, for example, gas, water, or centrifugalatomization to produce a metallic powder. In particular embodiments ofthe present invention, it can be advantageous to process a solidmaterial to form powder utilizing atomization techniques since suchprocessing can produce large amounts of stable, non-reactive powders ofa desired size range in a single step. Atomization methods can producespherical powders that can be especially advantageous since sphericalparticles can flow easily, allowing improved passage through a thermaldeposition device (see below). The spherical nature of powder particlesproduced from a hard steel ingot of alloy composition is shown in FIG.3.

In particular aspects of the present invention, formation of powderparticles by atomization can form powder particles that comprise atleast some amorphous microstructure. Due to the high glass formingabilities of compositions of the present invention, rapid solidificationduring atomization allows direct production of amorphous glassparticles. In particular embodiments it can be desirable to produceamorphous particles and thereby limit or eliminate the need to remeltthe particles during subsequent deposition. Particular compositionsprocessed by methods of the present invention can produce powders thatcomprise up to 100% amorphous structure.

As shown in FIG. 2, metallic powder from step (F), can be formed frommolten alloy from step (D) according to methods of the present inventionwithout the inclusion of solidification step (E). Such direct powderformation can be achieved by utilizing rapid solidification methods suchas radiative cooling, convective cooling, or conductive cooling, oralternatively by any of the atomization methods discussed above withrespect to processing of a solid metallic material into powder form. Theadvantages discussed above with respect to atomization of the solidmaterial apply equally to atomization of a molten alloy according tomethods of the present invention.

Prior to a surface application step (H) of FIG. 2, the metallic powderof step F can be further processed by classification (sorting the powderbased on particle size (not shown)). Such classification can comprise,for example, sequential sieving and air classification steps. Particlesizes for powders produced by methods of the present invention cancomprise sizes from between about 10 μm to about 450 μm. Particleclassification of the powder can be used to obtain a specific ofparticle size or range of sizes useful for a chosen material depositiontechnique. In particular embodiments, classification can be used toproduce a powder comprising a particle size of from about 10 to about100 microns.

Still referring to FIG. 2, a powder produced by methods of the presentinvention can optionally be utilized for production of a wire in step(G), which can, in turn, be used for application to a surface in step(H). Wire formation step (G) of FIG. 2 is discussed in more detail withreference to FIGS. 4 and 5.

First referring to FIG. 4, wire formation can comprise providing a metalstrip 20 that can have a first composition, and providing a powder 22that can have a second composition. The composition of the metal strip20 and the composition of powder 22 can be combined to form a desiredwire composition for subsequent deposition or other applications. Powder22 is not limited to a specific powder and can comprise, for example, apowder produced by methods of the present invention discussed above. Thecomposition of metal strip 20 is not limited to any specific compositionand can be chosen to supplement the composition of powder 22 to form thedesired wire composition.

Metal strip 20 can be combined with powder 22 and further processed toform wire 24 as shown in FIG. 5. The combining of the metal strip 20 andthe powder 22 can comprise, for example, forming a cored wire utilizingconventional rolling/extrusion techniques wherein the powder materialforms a core 28 and the metal strip 20 forms a sheath 26 around core 28.Wire 24 is not limited to a specific diameter and can comprise, forexample, a diameter of from about 0.035 inch to about 0.188 inch. Inparticular embodiments, a preferred wire diameter can be 0.0625 inch.

A total composition of wire 24 comprising the combined compositions ofcore 28 and sheath 26, can include at least 55% iron by weight. Thetotal composition of wire 24 can preferably comprise fewer than elevenelements. In particular embodiments, the total composition of wire 24can consist essentially of the fewer than eleven elements. Preferably,the total composition of wire 24 can comprise or can consist essentiallyof from two to seven elements in addition to the iron. Elements otherthan iron present in the total composition can include at least oneelement selected from the group consisting of C, B, P, and Si. Inparticular embodiments wire 24 can comprise two, three or all of C, B,P, and Si. Wire 24 can, for example, comprise C, Si and B present in thetotal composition at an atomic ration of B₁₇C₅Si₁. The total compositioncan further contain one or more of W, Mo, Cr, Mn, Al and Gd.

Exemplary total compositions that can be comprised by wire 24 include:Fe₆₃Mo₂Si₁, Fe₆₃Cr₈Mo₂, Fe₆₃Mo₂Al₄, (Fe_(0.8)Cr_(0.2))₈₁B₁₇W₂,(Fe_(0.8)Mo_(0.2))₈₃B₁₇, Fe₆₃B₁₇Si₁, Fe₆₃Cr₈Mo₂C₅, Fe₆₃Mo₂C₅, Fe₈₀Mo₂₀,Fe₆₃Cr₈Mo₂B₁₇, Fe₈₃B₁₇, Fe₆₃B₁₇Si₅, Fe₆₃B₁₇C₂, Fe₆₃B₁₇C₃Si₃,(Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂, Fe₆₃B₁₇C₃Si₅, Fe₆₃B₁₇C₂W₂, Fe₆₃B₁₇C₈,Fe₆₃B₁₇C₅, (Fe_(0.8)Cr_(0.2))₇₈Mo₂W₂B₁₂C₅Si₁, Fe₆₃B₁₇C₅W₅, Fe₆₃B₁₇C₅Si₅,(Fe_(0.8)Cr_(0.2))₇₆Mo₂W₂B₁₄C₅Si₁, (Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂,Fe₆₃Cr₈Mo₂B₁₇C₅, (Fe_(0.8)Cr_(0.2))₇₅Mo₂B₁₇C₅Si₁, Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄,(Fe_(0.8)Cr_(0.2))₇₅W₂B₁₇C₅Si₁, Fe₆₃B₁₇C₅Si₁,(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₇C₅Si₁, (Fe_(0.8)Cr_(0.2))₇₂Mo₂W₂B₁₇C₅Si₁Gd₁,(Fe_(0.8)Cr_(0.2))₇₁Mo₂W₂B₁₇C₅Si₁Gd₂, and(Fe_(0.8)Cr_(0.2))₇₄Mo₂W₂B₁₇C₄Si₁.

The powder used for wire formation is not limited to a specificmicrostructure and can comprised from about 0 to about 100% amorphous(metallic glass) structure. Preferably the powder utilized for wireformation will comprise a composition that, when alloyed with themetallic wire sheath, will produce an alloy composition capable ofmetallic glass formation. The final composition of wire produced by thepresent invention can preferably comprise a volume fraction contributedby powder of from about 10% to about 60%.

The particle size range for powders utilized in wire formation accordingto methods of the present invention is not limited to a specific value.Since wire formation does not require a specific powder size, wireformation according to methods of the present invention can utilize anynon-classified powders or powder classification including sizes that areoutside the preferred particle size ranges for various powder depositiontechniques.

Referring again to FIG. 2, the powder from step (F) or the wire fromstep (G) can be utilized to treat a surface in step (H). Metallicmaterial in powder form or in wire form can be applied to a surface instep (H) to form a layer or coating over the surface. Application of apowder or wire feedstock according to methods of the present inventionis described in more detail with reference to FIG. 6.

As shown in FIG. 6, a substrate 50 is provided for treatment of asurface 51. Surface 51 can comprise a metal surface such as, forexample, a conventional steel surface, an aluminum surface, a stainlesssteel surface, a tool steel surface or any other metallic surface.Alternatively, surface 51 can comprise a non-metallic material such as,for instance, a ceramic material. Powder or wire, for example powder orwire produced by the methods discussed above, can be used for feedstockfor deposition onto surface 51. Exemplary surface treatment techniquesfor deposition of feedstock material onto surface 51 include thermaldeposition techniques where feedstock is fed into a deposition device52. The feedstock can be converted to a spray 54 and sprayed ontosurface 51 to form a layer of material 56. Thermal deposition is notlimited to a specific technique, and can comprise, for example, a highpressure plasma system, a low pressure plasma system, a detonation gunsystem, a diamond coat system, a high velocity oxy-fuel (HVOF) system, atwin roll or single roll wire-arc system, or a high velocity wire-arcsystem. Examples of as-sprayed HVOF coatings of compositionFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ are shown in FIG. 7.

Prior to any subsequent treatment, as-sprayed layer 56 can comprise amicrostructure that includes at least some metallic glass. The amount ofamorphous structure within layer 56 will depend upon the depositionmethod, the deposition conditions, and the composition of the feedstockmaterial. As-sprayed, layer 56 can comprise a hardness of greater thanabout 9.2 GPa. Typically, layer 56 will comprise a hardness of betweenabout 9.2 GPa and about 15.0 GPa.

Hardness of an as-sprayed layer can be affected by porosity. It can beadvantageous to produce a layer or coating comprising a low porositysince increased porosity of a material can result in a correspondingdecrease in hardness of the material. As shown in FIG. 8, layer 56 canhave a porosity of as low as 0.06%. Typically, layer 56 will comprise aporosity of less than or equal to about 5% (corresponding to a layerdensity of greater than or equal to about 95%). FIG. 9 shows porositiesof (Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ coatings formed by threedifferent coating deposition techniques. The plasma coating shown inPanel A has a porosity of 0.9%, the HVOF coating in Panel B has aporosity of 0.7%, and the wire-arc coating shown in Panel C has aporosity of 3.3%. Table 2 reports the determined hardness for each ofthe three layers shown in FIG. 9. As will be understood by those skilledin the art, porosity of layer 56 can be increased, if desired, byincorporation of oxygen during the spray deposition of the layer, or byspraying with non-optimized spray parameters. It is sometimes desirableto have a higher porosity layer, for example to absorb oil.

TABLE 2 Properties of Coatings Produced by Various Spray Techniques HVOFPlasma Wire-arc PROPERTY Coating Coating Coating Porosity (%) 0.7 0.93.3 Hardness as-sprayed 10.0 GPa 11.0 GPa 12.7 GPa Hardness after 1 hrat 14.5 GPa 13.5 GPa 13.5 GPa 700° C.

X-ray diffraction studies performed on the free surface side of a singleas-sprayed, 330 micrometer thick layer show a lack of long range orderedmicrostructure as shown in FIG. 10, thereby indicating an amorphousstructure of the coating. As-sprayed layer 56 can comprise somemeasurable amorphous structure, can comprise primarily amorphousstructure (greater than 50% of the microstructure), or can comprise upto about 100% amorphous structure.

Due to the lack of long range ordered microstructure in metallic glass,the presence of metallic glass allows layer 56 to be formed in theabsence of any interfacial layer (such as bond coat), between coatinglayer 56 and surface 51, as shown in FIG. 6. An interfacial layer is notrequired since there is little or no crystal structure mismatch betweenthe material of surface 51 and coating layer 56 due to the presence ofamorphous microstructure within layer 56. Although FIG. 6 shows anabsence of an interfacial layer, it is to be understood that theinvention encompasses embodiments wherein an interfacial layer isprovided (not shown).

Although FIG. 6 shows a single layer 56, it is to be understood that thepresent invention encompasses a coating comprising a multi-layerthickness (not shown). As-sprayed layer 56 can comprise a multi-layerthickness of from about 25 microns to about 6500 microns. If powderfeedstock is utilized, layer 56 can preferably comprise a multi-layerthickness of from about 250 microns to about 350 microns. If wirefeedstock is utilized, layer 56 can preferably comprise a multi-layerthickness of from about 750 microns to about 1500 microns.

A coating comprising a multi-layer thickness can be formed by, forexample, sequentially depositing individual layers according to themethods described above. X-ray diffraction scans of the free surfaceside (FIG. 11A) and the substrate surface side (after delamination, FIG.11B) of a 1650 micron thick, multilayer coating show that an amorphousstructure was maintained during a multilayer plasma-deposition process.FIG. 12 shows an x-ray scan indicating the amorphous structure of a ¼inch thick multilayer coating formed by twin-roll wire arc spraydeposition.

Differential thermal analysis (DTA) was performed to show the glass tocrystalline transformation for an atomized powder feedstock, an HVOFcoating and a plasma spray coating, of the compositionFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄. The DTA scans shown in FIG. 13, combined withdifferential scanning calorimetry (DSC) measurements, indicate that thepowder feedstock comprised 46% glass structure, the HVOF coatingcontained 41% glass structure, and the plasma coating contained 86%glass structure. The DSC trace shown in FIG. 14 was obtained from a ¼inch thick wire-arc coating of the composition Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄.

In addition to comprising a substantial hardness of at least about 9.2GPa, as-sprayed layer 56 can comprise a substantial toughness that isincreased relative to a toughness of the cooled-alloy solid mass form ofthe corresponding composition (discussed above). For example, when amaximum density is achieved as-sprayed layer 56 can comprise a tensileelongation up to about 60%.

Referring again to FIG. 2, once a metallic material has been applied toa surface in step (H), the metallic material can be further treated instep (I) to devitrify some or all of the metallic glass present in themetallic material to form crystalline having nanocrystalline grain size.Devitrification step (I) can result in an increased hardness of thedevitrified layer relative to the as-sprayed layer.

Devitrification step (I) can comprise heat treatment of the as-sprayedlayer comprising heating to a temperature from above the crystallizationtemperature of the particular alloy to less than the melting temperatureof the alloy composition of the layer, and can comprises heating frombetween one minute to about 1000 hours. Devitrification step (I) willtypically comprise heating from about 550° C. to about 850° C. forbetween about ten minutes and about one hour.

Heat treatment of metallic glass material enables a solid state phasechange wherein the amorphous metallic glass can be converted to one ormore crystalline solid phases. The solid state devitrification ofamorphous glass structure enables uniform nucleation to occur throughoutthe amorphous material to form nanocrystalline grains within the glass.The metallic matrix microstructure formed by devitrification cancomprise a steel matrix (iron with dissolved interstitials) or a complexmulti-phase matrix comprising several phases, one of which is ferrite.The nanocrystalline scale metal matrix composite grain structure canenable a combination of mechanical properties that are improved comparedto the properties that would exist with larger grain sizes or with themetallic glass. Such improved mechanical properties can include, forexample, high strength and high hardness and for particular compositionsof the present invention can include a maintained or even increasedtoughness relative to materials comprising larger grain sizes orcomprising metallic glass.

The resulting structure of devitrified material can comprise nanoscalegrains comprising from about 50 to about 150 nanometer grain size.Additionally, the devitrified material can comprise second phaseprecipitates at grain boundaries having a precipitate size of on theorder of 20 nanometers. FIG. 15, FIG. 16 and FIG. 8 show TEM micrographsof the microstructure comprised by heat treated materials formed bymethods of the present invention. Referring to FIG. 15, thenanocrystalline microstructure of a devitrified material comprising(Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂ is shown after treatment at varioustemperatures for one hour. FIG. 15 also shows a selected areadiffraction pattern for each of the three treatment conditions. FIG. 16shows the nanocrystalline microstructure and selected area diffractionpatterns of a devitrified material comprising(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ after treatment at varioustemperatures for one hour.

FIG. 17 shows a TEM micrograph of the nanocrystalline microstructure ofa devitrified layer comprising Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ that was formedusing HVOF deposition followed by heat treatment for one hour at 750° C.The TEM indicates a nanoscale structure having grains from about 75 nmto about 125 nm with 20 nm second phase precipitates at the grainboundaries. The sample shown in FIG. 17 was used to obtain the x-raydiffraction data scan shown in FIG. 18, Panel A, which was, in turn,refined as shown in FIG. 18, Panel B, to identify the nanocompositestructure summarized in Table 3.

TABLE 3 Phase Information for Devitrified(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ Phase Crystal System Space GroupLattice Parameters (°) α-Fe Cubic Im3m a = 2.902 Fe₂B Tetragonal I4/mcma = 5.179, c = 4.299 Cr₂₃C₆ Cubic Fm3m a = 10.713

As shown in Table 4, a devitrified nanocomposite material according tomethods of the present invention can have a hardness that is increasedas much as 5.2 GPa relative to the corresponding glass material (priorto devitrification). As Table 4 indicates, methods of the presentinvention can be utilized for production of hard glass materials or hardnanocomposite materials that have increased hardness over thecorresponding ingot form even for compositions that have a hardness ofless than 9.2 GPa when produced in ingot form.

TABLE 4 Hardness of Alloys in Ingot, Glass, and Nanocomposite ConditionsHardness (GPA) Alloy Composition Ingot Glass Nanocomposite(Fe_(0.8)Cr_(0.2))₈₁B₁₇W₂ 4.6 10.3 15.3 (Fe_(0.8)Mo_(0.2))₈₃B₁₇ 5.1 10.515.0 (Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂ 10.8 11.0 16.2(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂ 12.3 11.3 15.2Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ 13.2 12.1 15.5

Various methods were utilized to measure properties of devitrifiedmaterials produced by methods of the present invention. The ability toadhere to an underlying material was tested by conventional testingmethods including drop-impact test, bend test and particle impacterosion test. The coatings were able to pass all three of these tests.FIG. 19 illustrates the elastic and plastic ductility (resiliency) of acoating comprising Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄. A steel strip that has beencoated with approximately 200 micron thickness of coating material byHVOF deposition is shown in Panel A. Panel B and Panel C show the lackof chipping, cracking or peeling away of the coating from the base metalupon deformation of the coated strip.

In FIG. 20, Panel A shows an approximately 200 micron thickFe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄ coating on a flat plate. As shown, the coatingdemonstrates high ductility and toughness since it is able to deformwith the base metal during repeated hammering on the coating side (PanelB) or repeated hammering on the substrate side (Panel C). Additionally,no observable cracking, chipping or pulling away of the coating wasdetected upon severe deformation of the plate (Panel D).

Tensile properties of coating produced by methods of the presentinvention were measured by forming metallic ribbons of the compositionto be tested. Both metallic glass ribbons (FIG. 21) and devitrifiedribbons (FIG. 22) were subjected to various strain rates at a number oftemperatures. The stress/strain curves for metallic glass show thatelongation as high as 60% is attainable (FIG. 21, Panel A). Thedevitrified ribbon can exhibit superplasticity, having a maximumelongation of up to about 180% (FIG. 22).

The methodology described herein can have application for a number ofuses including, but not limited to, such uses as protective coatings andhardfacing. In such applications, metallic coatings produced by methodsof the present invention can be used on surfaces of parts, devices, andmachines to protect such surfaces from one or more of corrosion,erosion, and wear. Such applications can utilize either as-sprayedcoatings comprising metallic glasses or devitrified material comprisingnanocomposite structure. Additionally, such applications can utilizecoatings having some metallic glass structure and some nanocompositestructure. Such partially-glass/partially-nanocomposite coatings can beformed by, for example, sequentially forming individual layers and heattreating only specific layers, or by sequentially forming one or morelayers and only heat treating a portion of the one or more layers.

Due to the hardness of as-sprayed metallic glass materials formed bymethods of the present invention, coatings can utilize the as-sprayedmaterial without further devitrification. In other applications where anincreased hardness is desired, full devitrification can be performed andcan achieve up to 100% nanocomposite microstructure comprising extremehardness. The increase in hardness produced by methods of the presentinvention can be achieved without an accompanying loss of toughness, andcan even be accompanied by an increased toughness.

In compliance with the statute, the invention has been described inlanguage more or less specific as to structural and methodical features.It is to be understood, however, that the invention is not limited tothe specific features shown and described, since the means hereindisclosed comprise preferred forms of putting the invention into effect.The invention is, therefore, claimed in any of its forms ormodifications within the proper scope of the appended claimsappropriately interpreted in accordance with the doctrine ofequivalents.

1. A method of forming a hardened surface on a substrate, comprising:providing a solid mass comprising a first hardness of greater than orequal to 10.3 GPa; processing the solid mass to form a powder; applyingthe powder to a surface of a substrate to form a layer having a secondhardness, at least some of the layer comprising metallic glass; andconverting at least some of the metallic glass to a crystalline materialhaving a nanocrystalline grain size of about 50 nm to about 150 nm andhaving second phase precipitates at grain boundaries having aprecipitate size of about 20 nm, the converting of the metallic glass toa crystalline material causing hardening of the layer to form a hardenedlayer having a third hardness of greater than or equal to 15.0 GPa thatis greater than the first hardness and greater than the second hardness.2. The method of claim 1, wherein the solid mass comprises an ingotform.
 3. The method of claim 1, wherein the powder comprises at leastsome amorphous structure.
 4. The method of claim 1, wherein theconverting of at least some of the metallic glass to a crystallinematerial comprises heating the layer to a temperature between about 600°C. and a melting temperature of the metallic glass.
 5. The method ofclaim 1, wherein the solid mass comprises a first toughness, wherein thelayer prior to the converting of at least some of the metallic glass toa crystalline material comprises a second toughness, and wherein thehardened layer comprises a third toughness, the second toughness and thethird toughness each being equal to or greater than the first toughness.6. The method of claim 1, wherein the solid mass comprises a compositionof from three to eleven elements, the composition comprising at leastabout 55 percent iron by weight, and at least two of B, C and Si.
 7. Themethod of claim 6, wherein the composition comprises fewer than nineelements.
 8. The method of claim 6, wherein the composition comprises atleast one transition metal.
 9. The method of claim 1, wherein the layeris formed on the surface of a substrate in an absence of an interfaciallayer.
 10. A method of forming a hardened surface on a substrate,comprising: providing a solid mass comprising a composition selectedfrom the group consisting of Fe₆₃Mo₂Si₁, Fe₆₃Cr₈Mo₂, Fe₆₃Mo₂Al₄,(Fe_(0.8)Cr_(0.2))₈₁B₁₇W₂, (Fe_(0.8)Mo_(0.2))₈₃B₁₇, Fe₆₃B₁₇Si₁,Fe₆₃Cr₈Mo₂C₅, Fe₆₃Mo₂C₅, Fe₈₀Mo₂₀, Fe₆₃Cr₈Mo₂B₁₇, Fe₈₃B₁₇, Fe₆₃B₁₇Si₅,Fe₆₃B₁₇C₂, Fe₆₃B₁₇C₃Si₃, (Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂, Fe₆₃B₁₇C₃Si₅,Fe₆₃B₁₇C₂W₂, Fe₆₃B₁₇C₈, Fe₆₃B₁₇C₅, (Fe_(0.8)Cr_(0.2))₇₈Mo₂W₂B₁₂C₅Si₁,Fe₆₃B₁₇C₅W₅, Fe₆₃B₁₇C₅Si₅, (Fe_(0.8)Cr_(0.2))₇₆Mo₂W₂B₁₄C₅Si₁,(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂, Fe₆₃Cr₈Mo₂B₁₇C₅,(Fe_(0.8)Cr_(0.2))₇₅Mo₂B₁₇C₅Si₁, Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄,(Fe_(0.8)Cr_(0.2))₇₅W₂B₁₇C₅Si₁, Fe₆₃B₁₇C₅Si₁,(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₇C₅Si₁, (Fe_(0.8)Cr_(0.2))₇₂Mo₂W₂B₁₇C₅Si₁Gd₁,(Fe_(0.8)Cr_(0.2))₇₁Mo₂W₂B₁₇C₅Si₁Gd₂, and(Fe_(0.8)Cr_(0.2))₇₄Mo₂W₂B₁₇C₄Si₁, the solid mass having a firsthardness, wherein the first hardness is greater than or equal to 10 GPa;processing the solid mass to form a powder; applying the powder to asurface of a substrate to form a layer having a second hardness, atleast some of the layer comprising metallic glass; and converting atleast some of the metallic glass to a crystalline material having ananocrystalline grain size of about 50 to about 150 nm and having secondphase precipitates at grain boundaries having a precipitate size ofabout 20 nm, the converting of the metallic glass to a crystallinematerial causing hardening of the layer to form a hardened layer havinga third hardness that is greater than the first hardness and greaterthan the second hardness, wherein the third hardness is greater than orequal to 15 GPa.
 11. (canceled)
 12. The method of claim 1, wherein theapplying the powder to the surface comprises at least one of plasmaspray thermal deposition, diamond jet thermal deposition andhigh-velocity oxy-fuel thermal deposition.
 13. The method of claim 1,further comprising: prior to the applying the powder to the surface,combining the powder with a metal strip to form a wire, the wire havinga final composition comprising at least 55% iron by weight and at leastone element selected from the group consisting of Si, C, P and B; andwherein the applying the powder to the surface comprises at least one oftwin-roll wire arc deposition, single-roll wire arc deposition andhigh-velocity wire arc deposition.
 14. A method of forming a hardenedsurface on a substrate, comprising: providing a solid mass comprising afirst hardness of greater than or equal to 10.3 GPa; processing thesolid mass to form a powder; applying the powder to the surface of ametal strip; rolling the metal strip to form a wire having an ironsheath and a powder core, the wire having a first diameter and having afinal composition comprising at least 55% iron by weight; extruding thewire to form a wire having a second diameter; applying the wire havingan iron sheath and a powder core to a surface of the substrate to form alayer having a second hardness, at least some of the layer comprisingmetallic glass; and converting at least some of the metallic glass to acrystalline material having a nanocrystalline grain size of about 50 nmto about 150 nm and having second phase precipitates at grain boundarieshaving a precipitate size of about 20 nm by melting at least some of themetallic glass, the converting of the metallic glass to a crystallinematerial causing hardening of the layer to form a hardened layer havinga third hardness of greater than 15.0 GPa.
 15. The method of claim 14,wherein the converting of at least some of the metallic glass to acrystalline material comprises heating the layer to a temperaturebetween about 600° C. and a melting temperature of the metallic glass.16. The method of claim 14, wherein the solid mass comprises a firsttoughness, wherein the layer prior to the converting of at least some ofthe metallic glass to a crystalline material comprises a secondtoughness, and wherein the hardened layer comprises a third toughness,the second toughness and the third toughness each being greater than thefirst toughness.
 17. The method of claim 14, wherein the solid masscomprises a composition of from three to eleven elements, thecomposition comprising at least about 55 percent iron by weight, and atleast two of B, C and Si.
 18. The method of claim 17, wherein thecomposition comprises fewer than nine elements.
 19. The method of claim14, wherein the layer is formed on the surface of a substrate in anabsence of an interfacial layer.
 20. The method of claim 14, wherein thesolid mass comprises a solid mass comprising a composition selected fromthe group consisting of Fe₆₃Mo₂Si₁, Fe₆₃Cr₈Mo₂, Fe₆₃Mo₂Al₄,(Fe_(0.8)Cr_(0.2))₈₁B₁₇W₂, (Fe_(0.8)Mo_(0.2))₈₃B₁₇, Fe₆₃B₁₇Si₁,Fe₆₃Cr₈Mo₂C₅, Fe₆₃Mo₂C₅, Fe₈₀Mo₂₀, Fe₆₃Cr₈Mo₂B₁₇, Fe₈₃B₁₇, Fe₆₃B₁₇Si₅,Fe₆₃B₁₇C₂, Fe₆₃B₁₇C₃Si₃, (Fe_(0.8)Cr_(0.2))₇₉B₁₇W₂C₂, Fe₆₃B₁₇C₃Si₅,Fe₆₃B₁₇C₂W₂, Fe₆₃B₁₇C₈, Fe₆₃B₁₇C₅, (Fe_(0.8)Cr_(0.2))₇₈Mo₂W₂B₁₂C₅Si₁,Fe₆₃B₁₇C₅W₅, Fe₆₃B₁₇C₅Si₅, (Fe_(0.8)Cr_(0.2))₇₆Mo₂W₂B₁₄C₅Si₁,(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₆C₄Si₁Mn₂, Fe₆₃Cr₈Mo₂B₁₇C₅,(Fe_(0.8)Cr_(0.2))₇₅Mo₂B₁₇C₅Si₁, Fe₆₃Cr₈Mo₂B₁₇C₅Si₁Al₄,(Fe_(0.8)Cr_(0.2))₇₅W₂B₁₇C₅Si₁, Fe₆₃B₁₇C₅Si₁,(Fe_(0.8)Cr_(0.2))₇₃Mo₂W₂B₁₇C₅Si₁, (Fe_(0.8)Cr_(0.2))₇₂Mo₂W₂B₁₇C₅Si₁Gd₁,Fe_(0.8)Cr_(0.2))₇₁Mo₂W₂B₁₇C₅Si₁Gd₂, and(Fe_(0.8)Cr_(0.2))₇₄Mo₂W₂B₁₇C₄Si₁.